One way to treat disease states due to malfunctioning organs is to effect the surgical transplantation of whole organs. Improvements in operative techniques and in methods for preventing organ transplant rejection have made commonplace the successful transplantation of organs such as the heart, kidney, and liver. Nevertheless, such procedures are still associated with a high degree of morbidity and mortality, besides being very expensive and requiring extensive perioperative care. The most significant factor restricting the applicability of whole organ transplantion operations, however, is the limited availability of donor organs.
Certain disease states involving organ failure can be successfully treated by replacing only a small proportion of the organ mass with populations of donor cells. Such donor cells (referred to herein as "cellular transplants") are obtained from a donor organ by mechanical disruption or enzymatic digestion of the parenchyma of a donor organ. Advances in cell culture techniques have made it possible to maintain donor cells such as hepatocytes in a viable and functional state in vitro for extended periods of time until they are transplanted into a recipient. Successful transfer of such cellular transplants into animal recipients has recently been demonstrated for both liver cells (See Rhim et al., Science 263, 1149 (1994)) and heart muscle cells (See Soonpaa et al., Science 264, 98 (1994)).
In order fully realize the advantages of cellular transplantation, the transplant procedure should be performed in a minimally invasive manner without the requirement of a surgical operation. Placement of the cellular transplants into the correct anatomic location, however, is critical if the cellular transplants are to function properly after implantation. The present invention is a system and method for accomplishing both of those objectives.
In accordance with the present invention, a transplantation tool (which may be, for example, an injection device such as a hypodermic injection needle or a catheter for delivering cellular transplants through an outflow port to an intraductal or other internal body site within which the catheter is disposed) is manipulated by a manipulator or catheter under computer control so as to deliver a predetermined amount of a fluid transplant medium containing cellular transplants to a select anatomical area of a patient's body as defined by location coordinates locating the select body area with respect to a structure supporting the patient. In one embodiment of the invention, the tranplantation tool is mechanically positioned by a robotic arm operating automatically in accordance with imaging information derived from a scanning system and fed to a computer. In other embodiments, the transplantation tool is positioned manually by an operator while a computer monitors the operation to provide a computer generated indication of when the tool is operatively positioned so as to effect the injection or other delivery of the transplant medium at a selected coordinate location of the body into select body or organ tissue thereof.
It is therefore a primary object of the present invention to provide a system and method for precisely delivering cellular transplants or other agents to a patient at selected anatomical locations.
It is a further object to provide a computerized method and system that enables user designation of selected anatomical locations for cellular transplant delivery via images generated by imaging devices which are stored in a computer and displayed to the user.
It is a further object to provide a system and method that automatically delivers cellular transplants to user selected locations under computer control.
Other objects, features, and advantages of the invention will become evident in light of the following detailed description considered in conjunction with the referenced drawings of a preferred exemplary embodiment according to the present invention.